fix: replace blocking play_audio with async generator yielding playback duration in gcloud tts

src/rspeech/play.py

@@ -30,16 +30,18 @@ import os
 import subprocess
 import sys
 import pygame 
-
+import time 
 
 
 async def play_audio_async(filename)
     pygame.mixer.init()
     pygame.mixer.music.load(filename)
+    time_start = time.time()
     pygame.mixer.music.play()
+    
     while pygame.mixer.music.get_busy():
-        await asyncio.sleep(0.1)
-        yield
+        duration = time.time() - time_start 
+        yield duration 
 
 
 def play_audio(filename):